Explanation:
On January 1
New Horizons encountered
the Kuiper Belt object nicknamed Ultima Thule.
Some 6.5 billion kilometers from the Sun, Ultima
Thule is the most distant world ever explored by a spacecraft
from Earth.
This historic image,
the highest resolution image released so far,
was made at a range of about 28,000 kilometers only
30 minutes before the New Horizons closest approach.
Likely the result of a
gentle
collision shortly after the birth of the Solar System,
Ultima Thule is revealed to be a contact
binary, two connected sphere-like shapes
held in contact by mutual gravity.
Dubbed separately by the science team Ultima and Thule, the larger
lobe Ultima is about 19 kilometers in diameter.
Smaller Thule is 14 kilometers across.